Protein Kinase A Regulatory Subunit Type IIβ Directly Interacts with and Suppresses CREB Transcriptional Activity in Activated T Cells

CD28 plays a critical role in T cell immune responses. Although the kinase Akt has been shown to act downstream of CD28 in T helper (Th)1 cytokine induction, it does not induce Th2 cytokines such as interleukin 4 (IL-4). We recently reported that phosphoinositide-dependent kinase 1 (PDK1) partially corrects the defect in IL-4 production present in CD28-deficient T cells, suggesting that PDK1 regulates IL-4 independently of Akt. We now describe a signaling pathway in which PDK1 targets IL-4 in the murine Th2 cell line D10. PDK1-mediated activation of this pathway is dependent on protein kinase A (PKA) and the nuclear factor of activated T cells (NFAT) P1 transcriptional element in the IL-4 promoter. PDK1 localizes to the immune synapse in a phosphatidylinositol 3-kinase–dependent manner, partially colocalizes with PKA at the synapse, and physically interacts with PKA. In RNA interference knockdown experiments, PDK1 is necessary for phosphorylation of PKA in T cells, as well as for activation of the IL-4 NFAT P1 element by the T cell receptor (TCR) and CD28. Phosphorylation of the critical PKA threonine residue is stimulated by engagement of TCR/CD28 via a PDK1-dependent mechanism. These findings together define a pathway linking the kinases PDK1 and PKA in the induction of the Th2 cytokine IL-4.

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Expression and mutation analysis of regulatory subunit Iα of protein kinase A in undifferentiated and anaplastic thyroid carcinoma

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-2004-819071 ◽

2004 ◽

Vol 112 (S 1) ◽

Author(s):

M Lippert ◽

SY Sheu ◽

K Worm ◽

M Wichert ◽

KW Schmid ◽

...

Keyword(s):

Protein Kinase ◽

Thyroid Carcinoma ◽

Protein Kinase A ◽

Mutation Analysis ◽

Anaplastic Thyroid Carcinoma ◽

Regulatory Subunit ◽

Kinase A

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Targeting the Regulatory Subunit R2Alpha of Protein Kinase A in Human Glioblastoma through shRNA-Expressing Lentiviral Vectors

Viruses ◽

10.3390/v13071361 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1361

Author(s):

Maira Zorzan ◽

Claudia Del Vecchio ◽

Stefania Vogiatzis ◽

Elisa Saccon ◽

Cristina Parolin ◽

...

Keyword(s):

Protein Kinase ◽

Protein Kinase A ◽

Lentiviral Vectors ◽

Brain Parenchyma ◽

Regulatory Subunit ◽

Glioblastoma Cells ◽

Cellular Models ◽

Therapeutic Setting ◽

Promising Target ◽

Kinase A

Glioblastoma is the most malignant and most common form of brain tumor, still today associated with a poor 14-months median survival from diagnosis. Protein kinase A, particularly its regulatory subunit R2Alpha, presents a typical intracellular distribution in glioblastoma cells compared to the healthy brain parenchyma and this peculiarity might be exploited in a therapeutic setting. In the present study, a third-generation lentiviral system for delivery of shRNA targeting the regulatory subunit R2Alpha of protein kinase A was developed. Generated lentiviral vectors are able to induce an efficient and stable downregulation of R2Alpha in different cellular models, including non-stem and stem-like glioblastoma cells. In addition, our data suggest a potential correlation between silencing of the regulatory subunit of protein kinase A and reduced viability of tumor cells, apparently due to a reduction in replication rate. Thus, our findings support the role of protein kinase A as a promising target for novel anti-glioma therapies.

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The crystal structure of yeast regulatory subunit reveals key evolutionary insights into Protein Kinase A oligomerization

Journal of Structural Biology ◽

10.1016/j.jsb.2021.107732 ◽

2021 ◽

pp. 107732

Author(s):

Nicolás González Bardeci ◽

Enzo Tofolón ◽

Felipe Trajtenberg ◽

Julio Caramelo ◽

Nicole Larrieux ◽

...

Keyword(s):

Crystal Structure ◽

Protein Kinase ◽

Protein Kinase A ◽

Regulatory Subunit ◽

Kinase A

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Overexpression of the regulatory subunit of protein kinase A increases heterologous protein expression in Pichia pastoris

Biotechnology Letters ◽

10.1007/s10529-020-02977-z ◽

2020 ◽

Vol 42 (12) ◽

pp. 2685-2692 ◽

Cited By ~ 1

Author(s):

Xihao Liao ◽

Wenyang Lin ◽

Nanzhu Chen ◽

Lu Li ◽

Dafu Huang ◽

...

Keyword(s):

Protein Kinase ◽

Pichia Pastoris ◽

Protein Expression ◽

Protein Kinase A ◽

Heterologous Protein ◽

Regulatory Subunit ◽

Heterologous Protein Expression ◽

Kinase A

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Protein Kinase A Signaling Pathway Regulates Transcriptional Activity of SAF-1 by Unmasking Its DNA-binding Domains

Journal of Biological Chemistry ◽

10.1074/jbc.m300705200 ◽

2003 ◽

Vol 278 (25) ◽

pp. 22586-22595 ◽

Cited By ~ 19

Author(s):

Alpana Ray ◽

Papiya Ray ◽

Nicole Guthrie ◽

Arvind Shakya ◽

Deepak Kumar ◽

...

Keyword(s):

Protein Kinase ◽

Dna Binding ◽

Protein Kinase A ◽

Signaling Pathway ◽

Transcriptional Activity ◽

Dna Binding Domains ◽

Binding Domains ◽

Kinase A

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The Role of Uncoupling Protein 1 in the Metabolism and Adiposity of RIIβ-Protein Kinase A-Deficient Mice

Molecular Endocrinology ◽

10.1210/me.2004-0194 ◽

2004 ◽

Vol 18 (9) ◽

pp. 2302-2311 ◽

Cited By ~ 21

Author(s):

Michael A. Nolan ◽

Maria A. Sikorski ◽

G. Stanley McKnight

Keyword(s):

Adipose Tissue ◽

Oxygen Consumption ◽

Protein Kinase ◽

Protein Kinase A ◽

Uncoupling Protein ◽

Mrna Level ◽

Regulatory Subunit ◽

Uncoupling Protein 1 ◽

Brown Adipose ◽

Kinase A

Abstract Mice lacking the RIIβ regulatory subunit of protein kinase A exhibit a 50% reduction in white adipose tissue stores compared with wild-type littermates and are resistant to diet-induced obesity. RIIβ−/− mice also have an increase in resting oxygen consumption along with a 4-fold increase in the brown adipose-specific mitochondrial uncoupling protein 1 (UCP1). In this study, we examined the basis for UCP1 induction and tested the hypothesis that the induced levels of UCP1 in RIIβ null mice are essential for the lean phenotype. The induction of UCP1 occurred at the protein but not the mRNA level and correlated with an increase in mitochondria in brown adipose tissue. Mice lacking both RIIβ and UCP1 (RIIβ−/−/Ucp1−/−) were created, and the key parameters of metabolism and body composition were studied. We discovered that RIIβ−/− mice exhibit nocturnal hyperactivity in addition to the increased oxygen consumption at rest. Disruption of UCP1 in RIIβ−/− mice reduced basal oxygen consumption but did not prevent the nocturnal hyperactivity. The double knockout animals also retained the lean phenotype of the RIIβ null mice, demonstrating that induction of UCP1 and increased resting oxygen consumption is not the cause of leanness in the RIIβ mutant mice.

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Complex effects of kinase localization revealed by compartment-specific regulation of protein kinase A activity

10.1101/2021.04.08.439038 ◽

2021 ◽

Author(s):

Rebecca LaCroix ◽

Benjamin Lin ◽

Andre Levchenko

Keyword(s):

Cell Migration ◽

Protein Kinase ◽

Protein Kinase A ◽

Kinase Activity ◽

Single Cells ◽

Regulatory Subunit ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Specific Regulation ◽

Kinase A

SummaryKinase activity in signaling networks frequently depends on regulatory subunits that can both inhibit activity by interacting with the catalytic subunits and target the kinase to distinct molecular partners and subcellular compartments. Here, using a new synthetic molecular interaction system, we show that translocation of a regulatory subunit of the protein kinase A (PKA-R) to the plasma membrane has a paradoxical effect on the membrane kinase activity. It can both enhance it at lower translocation levels, even in the absence of signaling inputs, and inhibit it at higher translocation levels, suggesting its role as a linker that can both couple and decouple signaling processes in a concentration-dependent manner. We further demonstrate that superposition of gradients of PKA-R abundance across single cells can control the directionality of cell migration, reversing it at high enough input levels. Thus complex in vivo patterns of PKA-R localization can drive complex phenotypes, including cell migration.

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